Metamath Proof Explorer


Theorem s7cld

Description: A length 7 string is a word. (Contributed by Mario Carneiro, 27-Feb-2016)

Ref Expression
Hypotheses s2cld.1 ⊢ ( 𝜑 → 𝐴 ∈ 𝑋 )
s2cld.2 ⊢ ( 𝜑 → 𝐵 ∈ 𝑋 )
s3cld.3 ⊢ ( 𝜑 → 𝐶 ∈ 𝑋 )
s4cld.4 ⊢ ( 𝜑 → 𝐷 ∈ 𝑋 )
s5cld.5 ⊢ ( 𝜑 → 𝐸 ∈ 𝑋 )
s6cld.6 ⊢ ( 𝜑 → 𝐹 ∈ 𝑋 )
s7cld.7 ⊢ ( 𝜑 → 𝐺 ∈ 𝑋 )
Assertion s7cld ( 𝜑 → ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 𝐺 ”⟩ ∈ Word 𝑋 )

Proof

Step Hyp Ref Expression
1 s2cld.1 ⊢ ( 𝜑 → 𝐴 ∈ 𝑋 )
2 s2cld.2 ⊢ ( 𝜑 → 𝐵 ∈ 𝑋 )
3 s3cld.3 ⊢ ( 𝜑 → 𝐶 ∈ 𝑋 )
4 s4cld.4 ⊢ ( 𝜑 → 𝐷 ∈ 𝑋 )
5 s5cld.5 ⊢ ( 𝜑 → 𝐸 ∈ 𝑋 )
6 s6cld.6 ⊢ ( 𝜑 → 𝐹 ∈ 𝑋 )
7 s7cld.7 ⊢ ( 𝜑 → 𝐺 ∈ 𝑋 )
8 df-s7 ⊢ ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 𝐺 ”⟩ = ( ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 ”⟩ ++ ⟨“ 𝐺 ”⟩ )
9 1 2 3 4 5 6 s6cld ⊢ ( 𝜑 → ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 ”⟩ ∈ Word 𝑋 )
10 8 9 7 cats1cld ⊢ ( 𝜑 → ⟨“ 𝐴 𝐵 𝐶 𝐷 𝐸 𝐹 𝐺 ”⟩ ∈ Word 𝑋 )